If you want to avoid spending too much on a cruise, timing — and a dose of good luck — is everything. Like airfares, cruise fares fluctuate one day to the next based on supply, demand and other factors. The result? People pay different rates for the same trip. Here are some tips (most involving timing) that will help you improve your chances of landing a decent fare.

Learn how to spend less on your next cruise. — Fuse/Getty Images

1. Book Early
Many cruise lines offer so-called early-bird fares. Book six to 12 months in advance, and you can save in the range of 25 percent to 50 percent off the published "brochure" rates. In addition to saving money on the cruise, another advantage to booking this far out is that you can also book your air and hotel early, when rates may be less expensive. Plus, you get first dibs on travel dates, itineraries and cabin selection — a good thing since the cheapest and most expensive cabins sell out first.

2. Wait Until the Last Minute
This might, given the first tip, seem counterintuitive. But, once again, timing (early or late) is key. Cruise fares generally go up as a sailing date draws nearer — unless a particular sailing isn't selling. When it's 60 to 90 days before a sailing, the cruise line begins to panic. That's when you see crazy low fares such as a week in the Caribbean for $499 or less. Discounts can top 50 percent as the cruise line attempts to fill berths. Just be aware that booking later might mean a limited choice of travel dates, itineraries and types of cabin.

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